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Radar reveals two moons orbiting asteroid Florence

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Re: Radar reveals two moons orbiting asteroid Florence

#21
post #15
post #5

Imagine hijacking a 100-meter moon made of rare earth metals like gold, platinum, rhodium, ruthenium, iridium, etc. etc. More than enough to under write the mission and pay for a moon base.

If we go grab a moon sized ball of gold, gold will lose most of its value. It'll be the next Aluminium.

I never bought that argument. World gold production is about 100-200 billion per year. Just hold onto your meteor and sell 50 billion worth per year for the next 200 years.

Re: Radar reveals two moons orbiting asteroid Florence

#22
post #3

Earlier quoted context omitted.

> Is the 'light' reflecting off the asteroid emitted from the sun? I had never seen or even knew radar could distinguish value like what is shown here. Yes it's emitted from the sun, it's clear given that the time-lapse shows "Inner moon eclipsed" when passing behind the site of the asteroid that is not lit.

I was always under the assumption that with Radar images that it didn't rely on a light source as technically the radar is the source. So that the impression that there is a light an dark side was based purely on the motion towards and away from the receiver. But, you have pointed out something interesting and that would appear to indicate other wise. The clear rotation independent of source already shows that I am w…

This thread is very confused.

There are two things: the radar images are created with radio waves emitted by the radar installation. The second thing is that the visualisation shows a light source. They are unrelated to each other. I assume that the light source was added during rendering of the film and that it approximates the sun.

Re: Radar reveals two moons orbiting asteroid Florence

#23
post #16
post #15

Earlier quoted context omitted.

If we go grab a moon sized ball of gold, gold will lose most of its value. It'll be the next Aluminium.

That much gold would still be worth it for electronic and spaceflight applications. Gold's like a better copper or silver there. And let's not forget the most important application, stereo plug connectors. For platinum or iridium, making it cheaper there would enable all sorts of catalytic chemical processes that are prohibitively expensive now. If abundant enough, new demand will keep the bottom of the market from f…

Gold is already not a major expense in electronics. Platinum is currently cheaper than gold. Most pgm catalysts are capable of ~< .1% catalyst loading (e.g. monsanto and cativa processes), and the catalytic metals are easily recovered.

Re: Radar reveals two moons orbiting asteroid Florence

#24
post #20
post #11

Earlier quoted context omitted.

The trick is getting it through the atmosphere intact.

Not a real problem, you'll only lose the outermost layers going through the atmosphere. The biggest problem is what happens when it lands. And also what happens to whatever it lands on.

You can double selling asteroid insurance.

Re: Radar reveals two moons orbiting asteroid Florence

#25
post #5

Imagine hijacking a 100-meter moon made of rare earth metals like gold, platinum, rhodium, ruthenium, iridium, etc. etc. More than enough to under write the mission and pay for a moon base.

Pet peeve:

> rare earth metals like gold, platinum, rhodium, ruthenium, iridium

Not one of those is a rare earth metal. The complete list of rare earth metals:

cerium (Ce), dysprosium (Dy), erbium (Er), europium (Eu), gadolinium (Gd), holmium (Ho), lanthanum (La), lutetium (Lu), neodymium (Nd), praseodymium (Pr), promethium (Pm), samarium (Sm), scandium (Sc), terbium (Tb), thulium (Tm), ytterbium (Yb), yttrium (Y).

Rare earths are also, despite the name of the group, not particularly rare or expensive, and it would never make sense to go mine for them in space. (The short-lived supply crunch that brought them into public eye was caused by the Chinese first effectively subsidizing supply to the point where all other suppliers had to close, and then restricting exports. Since mines take several years to spin up, this caused some disruption until production in the rest of the world caught up. Supplies of REE are found practically everywhere.)

I know that you didn't actually mean rare earths, you just meant rare metals in general. However, calling them rare earths is approximately as wrong as calling C# C or calling Javascript Java. It's really grating.

Re: Radar reveals two moons orbiting asteroid Florence

#26
post #15

Earlier quoted context omitted.

If we go grab a moon sized ball of gold, gold will lose most of its value. It'll be the next Aluminium.

I got a chuckle out of the Hobbit movie, where Smaug's gold treasure was so enormous the dwarves would be rendered penniless if they tried to spend it :-) There is precedent. When the Spanish extracted all that gold and silver from South America and shipped it back to Spain, all they got was inflation.

And a very large fleet of ships.

Re: Radar reveals two moons orbiting asteroid Florence

#28

How about we have satellites orbiting asteroids for a piggy back ride and then getting off the orbit when they are near a point of interest? My guess is the gravity would be too feeble.

You would need to first match the asteroid's velocity, and by then you do not really need the asteroid. But something very similar to your idea is used constantly for interplanetary travel - gravity assist which uses other bodies' gravity to accelerate and change direction.

Re: Radar reveals two moons orbiting asteroid Florence

#29
post #2

Is the 'light' reflecting off the asteroid emitted from the sun? I had never seen or even knew radar could distinguish value like what is shown here. I suppose terrestrial radar looks at much smaller objects and what it sees is emitted from the tower and bounced back in a straight line so that sort of makes sense. More info on the observatory: https://en.wikipedia.org/wiki/Goldstone_Solar_System_Radar

No, that's not showing light reflected from the sun. In the still image, the radar source (aka Earth) is to the left; in the animation it's at the top.

In the still image, the vertical dimension is the bearing of the transmitted radar signal, while the horizontal dimension is distance away from Earth, as computed by the time of flight of the radar signals. In the animation those are swapped.

Re: Radar reveals two moons orbiting asteroid Florence

#30

Earlier quoted context omitted.

I was always under the assumption that with Radar images that it didn't rely on a light source as technically the radar is the source. So that the impression that there is a light an dark side was based purely on the motion towards and away from the receiver. But, you have pointed out something interesting and that would appear to indicate other wise. The clear rotation independent of source already shows that I am w…

This thread is very confused. There are two things: the radar images are created with radio waves emitted by the radar installation. The second thing is that the visualisation shows a light source. They are unrelated to each other. I assume that the light source was added during rendering of the film and that it approximates the sun.

I don't think the visualisation shows any light source. The radar reflection from the asteroid just looks like it is "lit up"
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